Electrical terminal



. May 7, 1940. CQYNE I 2,200,059

ELECTRICAL TERMINAL Filed Jun 11, 1938 FIG. 3 l4 lNl ENTOR H. L. COYNE j. 22min m a/ X A TTORNEV Patented May 7, 1940 Q UNITED STATES PATENT OFFICE ELECTRICAL TERMINAL Howard L. Coyne, Bockville Centre, N. Y., assignor to Bell Telephone Laboratories, IncorporYatelcKl, New York, N. Y., a corporation of New Application June 11, 1938, Serial No. 213,209

4 Claims. (Cl. 175-21) This invention relates to electrical terminals In this invention, terminal structures and. arand more particularly to terminals adapted for rangements are provided wherein portions of the use on wire wound electrical devices. terminals are free to move relative to the spool- The object of the invention is-to provide a head to compensate for shrinkage of the coil terminal structure and an arrangement suitable structure and thus relieve the tension on the end 5 for use on wire wound electric devices subject to portions of the coil leading to the terminals. shrinkage and which will prevent breaking of the As shown in Figs. 1 and 2, an apertured spoolwire head I is supported on a core 2. In a complete A feature of the invention resides in the terstructure another spoolhead, not shown, but corminal structure and its manner of support in a responding to the spoolhead l is supported on 10 spoolhead. the core 2 and spaced from the spoolhead I. Sup- In the drawing, Fig. 1 is a side elevational View, p d 0n the C 2 d disposed between th partly in section, of a portion of a wire wound spoolheads is a coil 3 comprising various layers electrical device embodying this invention; 4 Of the W e W nd a d i e posed layers 5 of Fig. 2 is a view of the same portion of the sheet insulating material. A terminal 6 is supi5 device shown in Fig. 1 but taken after shrinkage ported in th p lhead l. The terminal 6 comhas occurred in a portion of the structure; p es an eyelet Portion 7 and a tab portion 3 Fig. 3 is a view in perspective of a portion of Conn y a bar portion e eyelet p a double-coil wire wound device embodying this tion I is flanged at N] to bear against the inner invention; face I! of the spoolhead l and the tubular part 20 Figs. 4 and 5 are views, in section, of portions of e eye t p o s loosely Set n an p of the device shown in Fig. 3, and taken on the e l2 p ov ded in the spoolhead I. An end p line 4-4 and 55, respectively; and tion l3 of the winding i is extended into the eye- Fig. 6 is a view in perspective and in exploded let portion I of the terminal and is suitably conform of portions of a double-coil wire wound e ed t e r s a by means of solder. 25 device of the type shown in Fig. 3. The bar portion 9 of the terminal 6 lies between In wire wound electrical devices where the an end of the coil 3 and the inner face of the winding is disposed on the core of a, spool type SDOOlhefid I. The tab portion 3 0f the terminal 6 support and terminals for the ends of the wire dS a an angle from the bar portion 9 d winding are supported on the spoolhead, shrinkthrough an ap e 14 in e DO ad l and 30 age of the Wound portion of the structure will p v es a conv n e y ar terminal p rsometimes cause severance of th ti n of tion for connecting to an electrical system. The wire leading to the terminals. This frequently tab Portion 3 y be anchored in t apeTtllre occurs in structures where strips of insulating I 4 y cement or other suitable means or y be material are alternated with various layers of simply he d therein y friction between the p 35 wire wound on the spool structure. The strips The eyelet po 7 and the bar portion of insulating material in some cases, for instance, ever, are quite free to move in the event of shrinkare made of sheet cellulose acetate. In other a e Occurring in t e Cel S nce the eyelet p cases they may comprise paper or other sheet tion 7 s y loosely Positioned in e perture insulating material impregnated and coated with the bar portion 9 and flange are p y 40 wax, cellulose acetate or other suitable insulating e d, un normal C d a nst the inner material or compound. The insulating material Surface H of the spoolhead y t e adj e t end may shrink with age or under the influence of a of e C011 change in temperature and thus cause a decrease When the C011 3 Shrinks y from t e p in the over-all length of the coil comprising the head as Shown in 2, the eyelet portion 1 45 winding of wire and the interposed layers of inof the terminal 6 follows the movement of the sulating material. The shrinkage of the coil Coil the bar portion 9 and e flange l0 also structure causes tension on the ends of the wire follow the movement of the 0011 3 and mOVe y winding leading to terminals supported on th from the inner face ll of the spoolhead I, the

spoolhead. Since the coil structure moves inportion 9 being Slightly fl ed. The rela- 60 wardly away from the spoolhead, the tension detively large aperture I! in the spoolhead perveloped in the portions of the wire winding leads tilting of e eyelet portion 7 d f ee moveing to the terminals is in some cases sufficient to ment of the eyelet portion When the coil 3 shrinks. cause severance of the wires and consequent dis- S e a portion of the terminal 5 follows the connection of the coil from a circuit. movement of the coil 3 when the coil shrinks away 55 from the inner face of the spoolhead, the end portion I3 of the wire winding is relieved of considerable strain that it would otherwise be subjected to were the eyelet portion secured to the spoolhead. The terminal structure and arrangement shown in Figs. 1 and 2, therefore, prevents breaking of the end portion I3 of the wire winding. I have found that this structure and arrangement also prevents breaking of the end portion I3 of the wire winding when the apparatus is being shipped or otherwise handled where the apparatus is subjected to jars or shocks such as would ordinarily cause breaking of a relatively small gauge wire.

In Figs. 3, 4, 5 and 6, the invention is shown as applied to a double-coil structure of the type found in telephone ringers. As shown in Figs. 3 and 6, the operating coils I5 and I6 are supported on the respective cores I1 and I8. End portions of the cores I1 and I8 project through respective spaced apertures I9 and 20 in a plate 2| of insulating material. The plate 2| serves as a spoolhead common to the coils I5 and I6. Another spoolhead (not shown since it forms no part of the invention) may be applied to the other end of the structure.

Supported in spaced relation in the plate 2| are double eyelet terminals 22, 23 and 2,4, the terminals 22 and 23 serving respectively as terminals for the coils I5 and I6 and the terminal 24 serving as a strap connection between the coils I5 and I6. The terminals 22 and 23 are alike in structure and each comprises, as shown in Fig. 4, eyelet portions 25 and 26 connected by a bar portion 21. Four spaced apertures are provided in the upper portion of the plate 2| for receiving the eyelet portions of the terminals 22 and 23, the apertures being arranged in pairs and each pair being spanned by a terminal. The eyelet portion 25 of the terminal 22 is positioned in an aperture 28 in the plate 2I and one end of the eyelet portion 25 is spun over lightly against the outer surface of plate 2| to form a flange 29 to hold the eyelet portion 25 loosely in place. The eyelet portion 26 is loosely positioned in an aperture 36 and is left free to move therein. The bar portion 21 of the terminal 22 is normally disposed against the inner face 3| of the plate 2 The eyelet portion 25 of the terminal 23 is positioned in an aperture 32 in the plate 2| and one end is spun over lightly against the outer face of the plate to form a flange 33 to hold the eyelet portion loosely in position. The eyelet portion 26 in the terminal 23 is loosely positioned in an aperture 34 in the plate 2| and is left free to move therein. The bar portion 21 of the terminal 23 normally bears against the inner face 3| of the plate 2|.

The terminal 24, as shown in Fig. 5, comprises eyelet portions 35 and 36 connected by a bar portion 31. The eyelet portions 35 and 36 are loosely positioned in the respective apertures 38 and 39 provided in a central portion of the plate 2| and are free to move therein. The bar portion 31 normally rests against the inner face 3| of the plate 2|. It is to be noted that the terminal 24 is left free to move relatively to the inner face of the plate 2| since the eyelet portions 35 and 36 are not spun over against the outer face of the plate 2|.

The terminals 22, 23 and 24 are applied to the plate 2| before the coils I5 and I6 and their respective cores I1 and I8 are applied to the plate 2|. When the coils I5 and I6 are applied to the plate 2| by inserting ends of the cores I1 and I8 in the respective apertures I9 and 20, ends of the coils I5 and I6 adjacent the inner face of the plate 2| bear against the terminals 22, 23 and 24 and press the bar portion 31 of the terminal 24 and the bar portions 21 of the terminals 22 and 23 against the inner face 3| of the plate 2|. Before the coils I5 and I6 are placed in this position, the ends of the windings of the coils l6 and I6 are thrust through the free eyelet portions of the terminals and are drawn forwardly of the front face of the plate 2| as shown in Fig. 6. After the ends of the windings have been brought forwardly through the free eyelet portions of the terminals, the wires are attached to the free eyelet portions of the terminals, for instance, by means of solder. One end portion 40 of the winding of the coil I6, for instance, is brought through the eyelet portion 26 of the terminal 23 and is connected thereto. The other end portion 4| of the winding of the coil I6 is brought through the eyelet portion 36 of the terminal 24 and is secured thereto. An end portion 42 of the winding of the 0011 I5 is brought through the eyelet portion 35 of the terminal 24 and is secured thereto. The other end portion 43 of the winding of the coil I 5 is brought through the eyelet portion 26 of the terminal 22 and is secured thereto. The spunover end portions 29 and 33 of the respective terminals 22 and 23 serve as points of connection for wires 45 and 44 of a circuit in which the coils I5 and I6 may be connected when in use. For the purpose of illustration and not in the sense of being a limitation to the invention, the coils I5 and I6 have been shown as being connected in series. Assuming that the connections have been made in accordance with the arrangement shown in Figs. 3 and 6, the circuit of the structure would be as follows: Incoming wire 44 to the eyelet portion 25 of terminal 23, bar portion 21 of terminal 23, eyelet portion 26 of terminal 23, end portion 46 of the winding of coil I6, the winding of coil I6, end portion 4| of the winding of coil I6, eyelet portion 36 of terminal 24, bar portion 31 and eyelet portion 35 of terminal 24, end portion 42 and coils of the winding of coil I5, end portion 43 of the winding of coil l5, eyelet portion 26 of terminal 22, bar portion 21 and eyelet portion 25 of terminal 22, to outgoing wire 45.

The coils I5 and I6 in the structures shown in Figs. 3 and 6 may have layers of sheet insulating material alternated with various layers of wire wound on the cores and be constructed along the lines of the coil 3 shown in Figs. 1 and 2. When the double-coil structure shown in Figs. 3 and 6 is first made, the ends of the coils adjacent the inner face 3| of the plate 2| are tightly pressed against the inner face of the plate. When the coils I5 and I6 shrink with age or under the influence of a change of temperature so that the ends of the coils adjacent the plate 2| move away from the inner face of the plate, the terminal 24 and portions of the terminals 22 and 23 will follow the movement of the coils enough to prevent breaking of the portions of the coils where they are led to the terminals. Under the shrinking movement above mentioned, the terminal 24 will move bodily in the direction of movement of the coils I5 and I6 and will take, for instance, the position shown in Fig. 5 with the bar portion 31 spaced from the inner face 3| of the plate 2| and the eyelet portions 35 and 36 extending a lesser distance through the respective apertures 38 and 39 than they did before the shrinkage occurred. The eyelet portions 26 of the terminals 22 and. 23 under the same condition will move in the direction of the coils I5 and I6, and the bar portions 21 will move away from the inner face SI 01' the plate 2| to the position shown in Fig. 4, the bar portions 21 being more or less flexed according to the extent of shrinkage of the coils l5 and I6.

From the foregoing description and as illustrated in the drawing it will be seen that in this invention a departure has been made from the usual practice of having end portions of the wire forming a-coil attached directly to terminal posts immovably supported in a spoolhead or in a plate of insulating material, and that the terminal or a portion thereof is made movable to compensate for changes in the length of the coil structure under changes in temperature and for relative movement of parts of the structure such as would occur under the influence oi jars or shocksto which the apparatus might be sub jected in transportation. The result oi. the invention is that with less breaking of parts in service and in transportation of the apparatus considerable savings in expense are effected.

What is claimed is: I

1. In a wire wound electrical device comprising a core, a wire winding on said core and an apertured plate of insulating material supported on said core adjacent an end of said winding, a terminal comprising two tubular eyelet portions and a bar portion connecting said eyelet portions, one of said eyelet portions being loosely positioned in an aperture in said plate and connected to an end of the wire winding and the other eyelet portion being supported in an aperture in saidplate and having end portions flanged over into engagement with opposite faces of said plate.

2. In a wire wound electrical device'comprising a coil built up of a plurality of layers of windings of wire and interposed layers of insulating material, a core supporting said winding and an apertured plate of insulating material supported on said core adjacent an end of said coil, a terminal comprising two tubular eyelet portions and a bar portion connecting said eyelet portions, said bar portion being between an end 01' said coil and an adjacent face of said plate, said eyelet portions projecting forwardly oi! said bar portion through apertures in said plate and at least one of said eyelet portions being loosely disposed in an aperture in said plate and connected to an end of the wire winding in said coil.

3. In a wire wound electrical device comprising an operating coil, a core supporting said coil and an apertured spoolhead supported on said core adjacent an end of said coil, a terminal comprising two spaced tubular eyelet portions and a bar portion extending from one eyelet portion to the other, said bar portion being disposed between said spoolhead and an adjacent end of said coil, said eyelet portions extending forwardly' of said bar portion and .within apertures in said spoolhead, one of said eyelet portions being iastened to said spoolhead and the other eyelet portion being loosely positioned in the spoolhead and electrically connected to an end oi. said coil.

4. In an electromagnetic device comprising a pair of operating coils, means for supporting said coils in parallel spaced relation and an apertured plate disposed adjacent ends of said coils and serving as a spoolhead common to said coils, a set of terminals for said coils, each of said terminals comprising a bar portion and spaced projections extending normal to the plane of said bar portion, said bar portions lying against an inner face of said plate and between said plate and said operating coils and said projections extending into apertures in said plate. one 01' said terminals being common to said coils and having its projections'loosely positioned in apertures in said plate and connected to end portions of said coils and each of the other terminals having one projection extending through an aperture in said plate and spun over against an outer face of said plate and another projection loosely positioned in an aperture in said plate and connected to an end of a coil.

- HOWARD L. COYNR. 

